جستجوی مقالات مرتبط با کلیدواژه « Ascorbate » در نشریات گروه « زراعت »

Among Iran's industrial and export products, saffron has found an important place as the most valuable agricultural product in the world. One of the ways to increase yield in saffron is to provide sufficient number of mineral elements needed by the plant. This research was conducted in order to investigate the effect of biofertilizers including seaweed extract and ascorbic acid on quantitative and qualitative traits of saffron in a farm in Shahrood and Shahrood University of Technology laboratory in 2021.

The experiment was conducted based on the randomized complete block design in three replications. Spraying consisted of seven levels (control: spraying with distilled water), 2, 3 and 4 mg/L of brown seaweed extract (Ascophyllum nodosum), 50, 100 and 150 mM ascorbic acid in the flowering stage. Seaweed extract was used under the Akadine, made in Canada, and ascorbic acid was produced by Merck, Germany. Spraying of the materials were done in three stages (20 february 2021, 5 and 19 march 2022) at 10 o'clock in the morning. During the growing season of the plant (from the fall of 2021 to the end of May 2022), no organic or chemical fertilizers were used either in the form of irrigation or in the form of soil. During this period, the use of herbicides was avoided. The number of four stages of irrigation was applied, similar to previous years. All the plots were irrigated at the same rate and in the form of flooding. Seaweed extract was used under the Akadine, made in Canada, and ascorbic acid was produced by Merck, Germany. Data analysis was done using SAS 9.1 software and the means were compared using LSD test.

The results showed that the number of saffron flowers increased with the application of seaweed extract and ascorbic acid compared to the control. The highest flower fresh weight was recorded in plants that were sprayed with 4 mg/L of seaweed extract. All levels of foliar spraying, except for the lowest level of each substance (2 mg/L of seaweed extract and 50 mM ascorbic acid) caused a significant increase in the dry weight of the stigma compared to the control. The highest stigma dry weight was recorded in plants that were sprayed with 100 mM ascorbic acid. Anthocyanin increased by 11.53, 28.84, and 23.07% in plants that received 2, 3, and 4 mg/L of seaweed extract as a foliar spray, respectively. Total phenol was significantly increased in plants that received 2, 3 and 4 mg/L of seaweed extract and 100 and 150 mM ascorbic acid. The highest amount of total phenol was equal to 6.34 mg/g dry weight, which was related to the plants that were sprayed with 3 mg/l of seaweed extract. The use of seaweed extract at all three levels of 2, 3 and 4 mg/L caused a significant increase in anthocyanin by 11.53, 28.84 and 23.07%, respectively, compared to the control. Among the measured effective substances of saffron, only safranal increased under the influence of seaweed extract. Although the use of ascorbic acid increased the amount of anthocyanin, this increase was not statistically significant.

The results of this research showed that the application of seaweed extract and ascorbic acid in the form of foliar spraying increased traits such as the number of flowers, fresh weight of flowers, anthocyanin and finally the dry weight of saffron stigma. In general, it can be said that the qualitative characteristics of saffron can be improved by using seaweed extract and ascorbic acid. Finally, within the scope of the research, it is suggested to use 4 mg/L of seaweed extract and 100 mM ascorbic acid to increase yield in saffron.

In order to investigate the effect of foliar spraying of ascorbate and gibberellin on pigment content and degradation biomarkers in the medicinal plant Salvia officinalis L. under salinity stress conditions, a research was carried out in 2013 in the municipal greenhouse of Region 15. The experiment was conducted as a factorial in the form of a completely randomized design in four repetitions. Experimental agents of salinity stress at 4 levels of zero, 25, 50 and 75 mM from NaCl source, ascorbate at two levels of 0 and 4 mM and gibberellin at two levels of 0 and 2 mM are considered. became The comparison of the simple effect of salinity stress showed that this factor caused a significant decrease in the amount of chlorophylls and an increase in degradation biomarkers, although in terms of d-tyrosine content, salinity values of 50 and 75 mM were in the same statistical group. The spraying of 4 mM ascorbate and 2 mM gibberellin caused the decrease of all biomarkers and the increase of photosynthetic pigments. The results of the comparison of the mean of the significant mutual effects showed that in the situation of no application of salinity stress, the use of ascorbate did not lead to an increase in carotenoids, but in moderate salinities (50 mM) and severe (75 mM) their consumption increased carotenoid.

The proper planting date is known as one of the most important agronomic programs to achieve the optimal yield in crops through increasing adaption of plants to environmental conditions and improving resource use efficiency. The synchronization of growth stages with climatic parameters in terms of rainfall, temperature, and humidity is considered as the main consequence of proper planting dates. One of the most basic methods for improving water consumption patterns in the agriculture sector is the accurate management of cropping and breeding methods, so the implementation of policies to change the pattern of cultivation based on comparative advantage, efforts to reduce the level of crop cultivation requiring high water consumption and developing drought-resistant plants. In this regard, water scarcity is a well-known factor in reducing quinoa yield under arid and semi-arid areas, which can seriously affect crop profitability. Thus, the present study aimed to evaluate the different planting dates and irrigation rounds on physiological traits and growth yield and component yields of quinoa under Mashhad climate.

The current study was conducted at the Faculty of Agriculture, Ferdowsi University of Mashhad, Iran, in 2020. The experiment was designed as a split-plot arrangement based on randomized complete block design with three replications: planting date (July 6th, July 23th, and August 6th) as main plots and water deficit regimes (7, 14, and 21-d intervals) as subplots. The experimental data were analyzed using SAS 9.4. The mean values were statistically compared according to the least significant difference (LSD) test at the level of 5%.

According to the results, decreasing water availability significantly caused an increase in chlorophyll a, chlorophyll b, and carotenoid contents. Also, leaf osmotic potential at the planting date of August 6th significantly decreased up to 39%, compared with the planting date of July 6th. It seems that in the case of increasing temperature, with increasing leaf osmotic potential, the plant resistance to environmental conditions would be improved. The content of soluble carbohydrates as well as the activity of ascorbate peroxidase and peroxidase enzymes were significantly affected by the interaction between planting date and irrigation. The highest amount of ascorbate peroxidase enzyme was observed in the 21-d irrigation cycle and planting date of August 6th. Ascorbate activity increased with increasing drought stress. The highest content of soluble carbohydrates was found on the date of planting on July 23th and the 14-d irrigation cycle. In addition, grain yield at the 21-d irrigation cycle decreased by 25% compared to the 7-d irrigation cycle. Moreover, the highest grain yield was obtained from the planting date of august 6th (544 g.m-2). Water shortage during the root development stage is a limiting factor against the optimal yield of quinoa

Based on the results, a planting date on August 6th with a 14-d irrigation cycle can be recommended to achieve the desired yield of quinoa along with reducing water consumption in the Mashhad region.

Due to study the effect of ascorbate foliar application on photosynthetic pigments, phenols and flavonoids of purslane under salinity stress conditions, an experiment was carried out in 2016 at Islamic Azad University, Yadgar-e-Imam Khomeini (RAH) Shahre Rey Branch and Pakdasht city, as factorial design based on Completely Randomized design with 4 replications, in which salinity stress in 3 levels (0, 70, 140 and 210 mM) and ascorbate foliar application in three levels (0, 10 and 20 mM) were considered. The results showed that except for the simple effect of salinity on flavonoid and phenol and the effect of ascorbate on carotenoids and other effects on evaluated traits were significant. The double interaction effect of experimental factors was significant only on chlorophyll b and carotenoids. Base of the finding the mean  comparison results indicated that foliar spraying of 20 mM ascorbate led to the highest  chlorophyll content, but there was no significant increase in carotenoids. The mean comparison interaction effects demonstrated that 210 mM and non using of ascorbate gained to maximum leaves carotenoids content (0.72 µg/ml), while no use of salinity water and 20 mM of ascorbate solution with µg/ml 4.24 ml produced the highest leaves chlorophyll b.

Introduction The growth and production of crop plants are strongly affected by various environmental stress. Salinity stress affects all stages of plant development including germination, bud growth, vegetative growth, flowering, and fruiting. During the past few years, several genes that encoding various structural and regulatory proteins have been used to produce tolerant plants of abiotic stress. Tolerant plants have been selected by improving our knowledge about molecular mechanism of stress tolerance in plants. Plants increase organic osmolytes such as proline, glycine betaine, polyols, alcoholic sugars, and soluble sugars to modulate osmotic stress. The P5CS gene (proline-5-carboxylate-synthase) is a key enzyme in the pathway for proline synthesis and this amino acid increases resistance of plants to salinity. Although there are many reports about the key role of accumulation proline in mechanism of salinity tolerance, a little information is available about physiological and non-enzymatic antioxidant response of transgenic plants by P5Cs overexpression in salt stress. Therefore, the aim of this study was to evaluate physiological and non-enzymatic antioxidant responses of transgenic and non-transgenic tobacco to salinity under in vitro culture. Materials and methods In order to achieve this goal, transgenic and non-transgenic plants were selected by PCR experiment with NPTII: P5CS proprietary primers. Consequently, the expression of the P5CS gene in transgenic plants was significantly higher than non-transgenic plants. To investigate the mechanism of salt tolerance in tobacco, transgenic and non-transgenic tobacco plants were grown on MS medium containing 0, 100, 150, 200 mM NaCl. After 4 weeks of treatments, fresh and dry weight, photosynthetic pigments, sodium and potassium, proline, phenol, anthocyanin, flavonoid, ascorbate, and hydrogen peroxide were measured. Results and discussion Based on the results, dry and fresh weight as well as chlorophyll content in transgenic plants decreased less than non-transgenic plant under salt stress. For example, the fresh weight of non-transgenic plants in the medium with 100 and 200 mM NaCl decreased by 47% and 33% and their dry weight decreased by 23 and 33%, respectively compared with transgenic plants. Total chlorophyll content of transgenic plants in the medium with 100, 150 and 200 mM salt was improved by 25%, 22%, and 41% compared with non-transgenic plants, respectively. Also, the leaves of transgenic plants accumulated less sodium than non-transgenic plants in response to salinity stress. By adding 100, 150 and 200 mM salt to medium, the level of sodium in transgenic plants decreased by 50%, 17%, and 18% compared with non-transgenic plants respectively. Moreover, the level of phenolic, anthocyanin and flavonoid compounds in the transgenic plants were less than non-transgenic plants by adding salt to medium. The proline content of both transgenic and non-transgenic plants increased in response to salinity. In addition, there was a significant increase in proline content of transgenic plants compared to non-transgenic plant under salt stress. The ascorbate content in transgenic and non-transgenic plants did not change significantly in response to salinity. However, the hydrogen peroxide decreased significantly in transgenic plants as compared with non-transgenic plants in salt stress. The results showed that the accumulation of hydrogen peroxide in transgenic plants in the medium with 100, 150 and 200 mM salt was 83%, 41%, and 23% lower than non-transgenic plants, respectively. So, it seems that transgenic and non-transgenic tobacco plants were salt tolerant and salt sensitive respectively. It has been suggested that high proline content may lead to salt tolerance in plants. According to our experiment, overexpression of P5CS gene increased proline content in other plants and improved salinity resistance in transgenic plants.

  Drought stress is one of the main limiting factors in plant production in semiarid regions; this is due to its oxidative stress. For evaluation of drought stress after pollination on some agronomic physiological factors in flag leaf and spikes of different wheat genotypes this study was designed as Randomized Complete Block Design with three replicates in Maragheh dryland research center in 2016. The first factor contains two levels of irrigation, control and drought stress (irrigation cut after pollination until the end of growth period) and the second factor contains different wheat genotypes (PTZ and TRK: tolerant, Manning and Sabalan: semi tolerant, Saratoves and RINA-11: sensitive). Drought stress decreased grain yield. Manning semi tolerant and Saratoves sensitive genotypes showed the highest and lowest grain yield. The activities of enzymatic (ascorbate peroxidase and glutathione reductase) and non- enzymatic (glutathione and ascorbate) antioxidants increased under drought stress. The highest and lowest ascorbate peroxidase enzyme activity was observed in flag leaf of TRK and Saratoves genotypes and in spikes of Manning and Saratoves genotypes. Also flag leaf and spikes of Manning and Saratoves genotypes showed the highest and lowest glutathione reductase enzyme activity. The highest glutathione and ascorbate content in flag leaf and spikes was related to TRK and Manning genotypes; the lowest content was observed in Saratoves. It seems that in spikes of Manning genotype, activation of enzymatic (ascorbate peroxidase and glutathione reductase) and non-enzymatic (glutathione and ascorbate) antioxidants had a key role in increase of tolerance to drought stress.

The present study sought to compare the effect of seed priming by hydropriming, ascorbate and calcium chloride (CaCl2) versus different concentrations of silver nanoparticles on two Iranian rice cultivars (Hashemi and Shiroodi) under drought stress. The experimental design, which was factorial, was completely randomized. The first factor was control (without priming), hydro-priming, 20 mg.L-1 calcium chloride, 20 mg.L-1 ascorbates and 20, 40 and 80 mg.L-1 of silver nanoparticles. The second factor was the drought stress, including control, -1.48 and -4.91 bars created by polyethylene glycol 6000 solutions. In plants without drought stress, the time required to reach 50% germination (T50) reduced to 34 and 54 percent under ascorbate and CaCl2 priming in the Hashemi and Shiroodi cultivars, respectively. In the drought stress condition, ascorbate and hydropriming pretreatments decreased T50 and the time required to reach 90% germination (T90) more than silver nanoparticles, especially in the Shiroodi cultivar. On the other hand, in comparison with other pretreatments, CaCl2 had an important role in increasing the growth factors in all of the drought stress treatments. Although 40 mg.L-1 silver nanoparticles increased the growth factors to some extent, it seems that higher levels of silver nanoparticles cause stress in seeds and therefore decrease the seed germination and growth of seedlings. By decreasing reactive oxygen species, Ascorbate improves the germination and by increasing plasma membrane efficiency, CaCl2 enhances the seedling growth under drought stress.

Summer savory (Satureja hortensis L.) is a genus of aromatic plants of the family Lamiaceae. There are about 30 different species called savories, which summer savory and winter savory are the most important in cultivation. Satureja species are native to warm temperate regions and may be annual or perennial (Hadian et al., 2008; Rechinger, 1982). Soil salinity is one of the main environmental stresses affecting the growth of plants and their yield (Allakhverdiev et al., 2000). Adaptation of plants to environmental stresses such as salinity performs by accumulation of metabolites as carbohydrates and proline (Sanito di Toppy and Gabbrielli, 1999). Ascorbic acid is a powerful antioxidant that leads to inhibition of the free radicals by reduction (Fecht Christoffers et al., 2003). Gibberellins are commercial mushroom cultures obtained from pure and natural product known that used in plants. There are four types of GA; the best known is gibberellic acid which has positive effect on metabolites related to salinity tolerance (Hedden and Proebsting, 1999).
Material and Due to study the effect of salinity stress on some non-enzymatic mechanisms of savory under ascorbate and gibberellin application, a pot experiment was done in a greenhouse located in Pakdasht region and Islamic Azad University, Eslamshahr and Yadegar-e-Imam Khomeini (RAH) Shahre-rey Branchs in 2013. The experimental design consisted of a sixteen treatments, arranged as factorial based on completely randomized design with four replications, giving a total of 64 pots. Five-weeks old savory plants were sprayed with ascorbic acid (0 and 4 mM) and gibberellins
(0 and 4 mM) before inducing salinity stress with different concentrations of saline water
(0, 25, 50 and 75 millimolar). Control plants were sprayed with distilled water. Saline water was delivered to plants twice a week and last for three weeks. The proline by Bates et al (1973), Protein by Bradford (1976) and soluble and non soluble carbohydrates by Kochert (1978) were determined. The obtained data were subjected to analysis of variance using Duncan Multiple Range Test (P≤0.05) using SAS software.
The results showed that, with the exception of ascorbate effect on shoot soluble carbohydrates, the other main effects of experimental factors were significant on all non-enzymatic mechanisms of savory tolerance. So the intense salinity showed the highest decreased in physiological traits such as shoot and root protein (304.93 mg/L and 147.71 mg/L) and shoot and root non soluble carbohydrates (11.27 and 8.25) and improved shoot and root proline (27.46 mg/L and 16.52 mg/L) and shoot and root soluble carbohydrates (18.49 mg/l and 16.32 mg/l) to decrease the harmful effects of salt stress. The results revealed that only triple interaction effects of experimental factors were significant on shoot soluble carbohydrates and shoot and root non soluble carbohydrates and protein. So, the shoot soluble carbohydrates and Shoot and root proline content has 8.23, 1.92 and 3.73 manifold increase than control in 75 mM NaCl and ascorbate and gibberellin foliar application alternatively. Therefore it can be concluded that shoot soluble carbohydrates is the most main non-enzymatic mechanisms of salt tolerance in savory especially in ascorbate and gibberellins foliar application. Some reports indicated that ascobate increased proline content in bean and pea (Alqrainy, 2007) and okra (Baghizadeh et al., 2009) that are coordinate to our findings. Hoda et al (2010) revealed that GA improved both Shoot and root soluble and non soluble carbohydrates as the best and rapid non-enzymatic mechanisms of stress tolerance in citrus.
The results showed that salinity stress increased shoot and root soluble carbohydrates and proline and reduced shoot and root non soluble carbohydrates and protein. At the same time, spraying 4 ascorbate and 2 mM GA affected all associated non-enzymatic traits to salt stress resistance, however the additive effect of GA was more than ascorbate.

Background and Nowadays, the application of antioxidants and plant growth regulators has discussed for decreasing the negative effect of different stresses. Ascorbic acid and sodium nitroprusside have substance caused witch the resistance to biotic and abiotic stresses. To evaluate the effect of ascorbic acid and sodium nitroprusside foliar application on some traits of safflower (Carthamus tinctorius), a field experiment was carried out in split plot factorial based on randomized complete block design in University of Shahrood.
Two levels of irrigation, including 8 days interval (well watered) and 16 days interval (water deficit stress) were in main plot, and foliar application of sodium nitroprusside in 3 levels (0, 50 and 100 µM) and ascorbic acid in 3 levels (0, 10 and 20 mM) were in sub plots. Stress treatment applied after plants establishment completely. The first foliar application of sodium niroprusside and ascorbic acid was performed in 63 and 65 days after sowing respectively and then repeat after 1 week.
Results showed that water stress decreased the capitol diameter, kernel weight, fertile capitol weight and number of seeds in capitol. Ascorbic acid foliar application increased fertile capitol weight and capitol diameter. The number of infertile capitol decreased by ascorbic acid and sodium nitroprusside foliar application. Ascorbic acid in 20 mM concentration increased significantly 0.69% in seed protein compared with control. The fertile capitol weight and capitol diameter increased significantly by sodium nitroprusside foliar application. Seed protein increased by application 100 µM concentration. Seed yield by application 100 µM sodium nitroprusside concentration was 13.2% more than control. The result showed that application 100 mM sodium nitroprusside concentration and 20 mM Ascorbic acid concentration contained fertile capitol weight and increasing 35.1 percentage compared with control.
20 mM Ascorbic acid and 100 mM sodium nitroprusside concentration can introduced as the best treatment compound.

Drought stress is a major environmental constraint which inhibits the growth of plants and limits crop production. Nowadays, the application of antioxidants and plant growth regulators has discussed for decreasing the negative effect of different stresses. Ascorbic acid and sodium nitroprusside have substance caused witch the resistance to biotic and abiotic stresses. Nitric oxide (NO) is a relatively stable free radical gas which may act as a key signaling molecule in plants and mediates various physiological, pathophysiological and developmental processes and recently it has been suggested that it is involved in plant response to environmental stress. It was found to play a crucial role in plant growth and development, starting from germination to flowering, ripening of fruit and senescence of organs. Ascorbate is a major metabolite in plants. It is an antioxidant and, in association with other components of the antioxidant system, protects plants against oxidative damage resulting from aerobic metabolism, photosynthesis and a range of pollutants. Recent approaches, using mutants and transgenic plants, are providing evidence for a key role for the ascorbate–glutathione cycle in protecting plants against oxidative stress.To examin the effect of ascorbic acid and sodium nitroprusside foliar application on seed yield, oil and some traits of safflower (Carthamus tinctorius), a field experiment design was carried out in split plot factorial based on randomized complete block in shahrood university in 2011.
The experimental treatment included two levels of irrigation, including 8 days interval (well watered) and 16 days interval (water deficit stress) were in main plot, and foliar application of ascorbic acid in 3 levels (0, 10 and 20 mM) and sodium nitroprusside in 3 levels (0, 50 and 100 µM) were in sub plot. The experimental design was split plot factorial based on randomized complete block in 3 replication. Stress treatment applied after plants establishment completely. The foliar application of sodium nitroprusside and ascorbic acid were performed in 63 and 65 days after sowing respectively and then repeat after 1 week.
Results showed that relative water content (RWC(, seed coat weight and number of seed per capitol decreased by water deficit stress. Stress increased seed coat to kernel ratio significantly. Number of capitol per plant increased (2.5capitol per plant on average) by ascorbic acid foliar application in 10mM concentration, but RWC decreased in this concentration of ascorbic acid. 1000 seed weight, seed yield (13.2%), oil yield (17.2%) and oil percentage (4.6%) increased significantly by sodium nitroprusside (100 µM) foliar application.
20 mM Ascorbic acid and 100 mM sodium nitroprusside concentration can introduced as the best treatment compound and it seems that the foliar application of sodium nitroprusside with appropriate concentration can be helpful in reducing stress intensity. which suggests that the protective effect of SNP is exerted through NO release. The protective effects of NO in drought stress may be due to its ability to counteract reactive oxygen species (ROS) and reduce the oxidative damages.

Environmental tensions cause increasing in active and Reactive Oxygen Species (ROS) in plants. Antioxidants materials such as querceitin and ascorbate have suitable chemical structure for free radicals deletion and increase plants resistant to tension. Oat (Avena sativa L.) have several medicinal and nutritive characteristics that can planted in saline soils by improving plant protective system against oxidative tension. The present study investigated the effect of exogenous quercetin and ascorbate separately and together on germination and antioxidant enzymes activity of Avena seedlings herb in mild and severs salinity tensions. Oat grains (promising cultivar) based on completely randomized design were treated to ascorbate in 0, 300 and 500 micro-mol, ascorbate 2 Mg -mol and NaCl in amounts of zero, 250 and 450 Mg-mol concentrations in Petri dish envirnoment. Germination percentage and antioxidant enzymes activity was evaluated in seedling. Adding quercetin and ascorbate increased germination percentage in comparison with salt in 450 Mg-mol. Adding quercitin and ascorbate the environment includes saline especially in 450 Mg-mol concentration increased peroxidase activity and decreased catalos enzyme activity. But had not significant changes in ascorbate peroxidase enzymes activity. Application of quercetin and ascorbate alone and together stimulate seed germination in high amount of salt (450 Mg-mol) that probably this reaction was due to increasing of peroxidase enzyme activity and deletion all kinds of active oxygen in Avena seedling.

Water deficiency in arid and semiarid areas is a limiting factor for plant growth، and plants have different mechanism for drought resistance. In this study، effects water stress in three levels of field capacity was examined on Cymbopogon Olivieri. According to the results، morphological features such as length and weight of root and shoot decreased in all treatments. Chlorophyll a content in 75%FC and 50%FC was higher than the control treatment، but 25%FC showed significant reduction. Clorophyll b and total chlorophyll had no significant differences in all treatments. Leaf anthocyanin content declined in 75%FC، but increased in 50%FC treatment، and also showed a significant increase in 25%FC treatment. The ascorbate content of leaf which is index of antioxidants showed a significant reduction as the water stress increased. Dehydroascorbate content showed a significant increase in 25%FC and 50%FC treatments. Proline content of leaves showed significant increase as the water stress increased. According to the results it can be mentioned that generally stress conditions caused growth reduction، but inducing the biochemical indices of tolerance.